What structure in the brain controls the chemical responses that signal the sex hormones to make us either male or female? a) All of these
b) The pituitary
c) The RAS
d) The adrenals

Which of the following occurs most often in a population when genetic variation and overproduction are present? some organisms have a lower reproductive success than others. some organisms have a higher reproductive success than others. some organisms have no reproductive success. some organisms do not have genetic variation.

Compare and contrast region e in the illustration above with region d. describe the physical characteristics of each region.

Which set of characteristics best describes sedimentary rock? a) largest type of rock, made of organic matter, hardest type of rock b) often contains layers, forms near sources of water, contains fossils c) least abundant type of rock, made of other rocks, made mostly of minerals d) most abundant type in earth's crust, made of magma/lava, contains no fossils